Forecaster summary - Issued 2019-10-08T00:03:32

The high energy electron flux (greater than 2MeV) is expected to vary between moderate and high (1e3 pfu) levels through the forecast period, at least during diurnal maximum periods, whilst fluence values are expected to remain below the Active (1e8 integrated pfu) threshold.

However, bearing in mind that there is great level of uncertainty surrounding this scenario, should the solar wind become slightly elevated on day 1 and 2 (08th and 09th) it would increase the high energy electron count, with corresponding fluence values likely to exceed the Active (1e8 integrated pfu) threshold on days 2 and 3 (09th and 10th) before coming back down on day 4 (11th).

The Met Office REFM output indicates a steady downward trend, whereas persistence from the previous rotation suggests an increase. Given what recently happened at STEREO A and the speed that was reached (up to 500km/s), there is certainly a chance of reaching Active levels, particularly on day 2 (09th) and 3 (10th).